Adjustable pulley v-belt transmission



July 24, 1951 H. J. SIEKMANN ET AL 2,561,712

h ADJUSTABLE PULLEY v-BELT TRANSMISSION Filed Aug. 25, 1949 l A l A v 1 il in3 m g I T A A O g a I u. o1 1 t* m 3 A T Z H 'n QD m A I CO LL ul o o. l (O O I n! Il mi 5g n1 53 t?) m gf; n INVENToRs. (C (L2 (u HAROLD J. S/EKMA/V/VAND GEORGE J. KA SSE/ MANN Patented July 24, 1951 ADJUSTABLE PULEEY-VQBELT TRANSMISSION Harold .J.. Siekmannz'and George-.J .1. Kasselmann, Cincinnati, Ohio, f assignors. .tol The.. R.`."K."' Le BlondMachine Tool Cincinnati, VOhioya corporation of Delaware Original- 1application:l September .f 1.0, 1\948,f-2Serial Nog-31 48,738,

September 2.6;.;1950., Divided and thisgapplicationzAugust 25;;1949, Serial "No, 1121274 3 Claims; (Cl. 744230217) '.TIhis lis.,aidivision'al-A application .offoriginal app'li'cation, Serial. Number, 48,738,.led September 10,11948, .now Patent Number` 2,523,397, `issued on September. 26, `1.950.`

...Thisfinvention pertains, toA improvements .in adjustable pulley V-belt transmissions-.and is par ticularlytdirected tomanV improved. construction forl theV.-.belt pulleysrto facilitate installation, removal, andA adjustment of the .driving belts.

Anothertobject .ofA this invention :is tog provide improvedl means. :in .av `V-belttransmission, `for adjusting,A the "Vebelt -pulleys for 1 proper operation of.. thebelts fori maximum f transmission of power@ whereA the shafts von which .the :pulleys are mounted,1l `arev located f `at iixed. centerdistan'ees and cannot otherwise be fremoved from their s upporting housing.

Further `features and advantages of this inventionyvvill` appear froma'detailed description of theidrawings'in which:

Figure 1 is anend view -otanadjustable pulley V-belt transmission incorporating the features of this invention;

Figure 2 is a sectional View@throughrthebbelt drive transmission indicated by. the` line 2--2 in Figure 1.

FigurePB is a view similar itoEigure 2 butshowing'gthe belts in fully stretched adjusted:y position.

For exemplary purposes this invention'islfshown applied-tto. afclose center. V.-belt transmission ha-ving a driving shaft `Ill carrying the,driving pulley or sheave I I which""drives"'through the V-belts I2, aridriven pulley orf/sheave' I3 iixed cin-wtheV driven shaft. UI. ..Installatiomaremovala.and adjustment of the driving belts I2 between the pulleys I I and I3 is accomplished by unique arrangement shown ybest in Figures 1, 2 and 3. On the drive shaft Il) is xed a pulley hub I 4a by a suitable lock nut I5. The outer periphery of the hub I4a has a continuous thread I6 extending along its entire diameter. An axially extending keyway Il adapted to receive a key I8 which is held in place by a suitable screw I 9 threaded into the hub I 4a at 20. On the outer threaded periphery of the hub Illa is a series of sheave forming rings 2l, 22 and 23, all of which may be rotated and moved along axially in any desired position on the periphery of the hub Ida. Slots are formed at six places in the threaded bores of the members 2l, 22 and 23, so that they may be rotated to bring a series of slots in alignment as at 25, Figure 1, and the key I 3 inserted therethrough as shown in Figure 2 to lock all of the collars 2|, 22 and 23 in desired axial driving position on the hub Ida.

"'On Vthe driverrsplndle- Ibis-'fixed a' pulley hub 26^`-of the pulley* I3 rwhich 'hasN a seres'ofithree V^'b`elt groovesl2'lformedtherein #A second pulley-"member 28 -is^- axially v`slidable in` driving engagement througtrakeyiZS" cri the diameter portionA `3 Ily of '-theapulleyf hub 26. 1abutment screws 3 I and draw-inf screwse 32 serveLl to accurately axially position thepulley` member 28= and tof-lock itf into'4 any'y adjusted# axial"A position.

Tlius; by. removing the variousI rings 2 It, 22 andA 23' from-'the pulley'hub Mw thevarious' V-belts I2' vrmay be readily installed' orrorremoved" from the' shaftsil ilfandllwithout disturbing'tlieir vcenteri distances-on their journalbearings. l"When the beltsl are fnevvrand h'avefjust been Lplacedion thepulieys as 1 shown bestjinf'Figure'i 2, the 'two pulley assembliesaassume thc-rrelationship shown: BelteA` 'is laositioned` in perfect' alignment-with both pulleys?. along theiline 33 whilebelts Blv and C are slightlyfdivergentWithiregard to the lines 34:` and" 352 at-the pulleyV I I The remainingbelts D and E are slightly divergent along the .lines `36 andi- 31 towardfthef pulley lI. "I'he'pulley 28`is movedAl ato maintain' this* genera relationship of the; :belis' 'Dfand l El with Yregard toy the `Vl-grooves 382 and tthe grooves-formed in the'pulley I I. thev beltsfwearl and it1is=desired to takeup tension inf Sthem,l1the twor sheave forming collars F'and G aremovedtoward each other` as shown in Fig-- ure. 3`,wstil1fmaintaining vthe* exact alignment of the i belt .iA-:.a1ong-intheoline` 33 :for both pulleys I I aiidll.v Thefouterfcollar` 2| fmarkedH is moved inwardly 'to' the lef tfas: Vshown 1in "Figurefl 3f1wliile the'fcollarll: =is moved toward fthe' right-toward the collar F `which results in a slightly convergent condition of the belt I2 toward the pulley I I. The sheave forming ring J is moved up against the ring I While the final ring K is moved up toward the ring J as seen in Figure 3. At the same time the pulley member 28 is moved to the right, Figure 3, to maintain a condition of slight convergence of the belts D and E toward the pulley II. Thus a wide range of selection of belt tensions may be obtained while at the same time avoiding the necessity of disturbing the shaft center distances or dismounting them in any way from the journal bearings and at the same time maintaining substantial correct alignment .of the belts in approaching and receding from the V- grooves in the pulleys.

While the apparatus herein disclosed and described constitutes a preferred form of the invention, it is to be understood that the apparatus is capable of mechanical alteration without departing from the spirit of the invention and that invention, what is claimed as new and desired to i,

be secured by United States Letters Patent is:

1. In a V-belt drive transmissionfor a pair of shafts having fixed centers, a means for adjusting, removing or replacing the VK-belts comprising a rst pulley means including a threaded pulley hub fixed on one of said shafts'having a threaded cylindrical diameter portion, a pluality of threaded sheave forming rings mounted on the threaded portion of said threaded pulley hub, a plurality of tion of said sheave forming rings, and a key carried in a keyway in the threaded periphery of said threaded pulley hub adapted to beinserted in the slots of said sheave forming rings when said rings have beenrotated on said threaded periphery to desired axial positions `on said threaded pulley hub, anda second pulley` means on the other of said shafts operatively related to the V-grooves formed .by said sheave form@ ing rings on said threaded Apulley hub, including a second` pulley fixed on said other -of said shafts, a plurality of V-grooves formed in the periphery of said second pulley, a second hub portion formed integral with saidsecond pulley having a peripheral bearing surface coaxial with the axis of rotation of said second pulley, a third :pulley mounted for axial movement on the periphery of said second hub portion, key means connecting said third pulley in driving relationship with said second hub portion, and screw adjusting means passing through said third pulley and engaging said second pulley to effect axial adjustment of said third pulley relativevto said second pulley and the V-grooves formed by said sheave forming rings on said threaded pul-A ley hub.

2. In a V-belt drive transmissionfor a pair of shafts having xed centers, a means for adjusting, removing or replacing the `V-belts comprising a rst pulley means including a threaded pulley hub fixed on one of said shafts having a threaded cylindrical diameter portion, a plurality'of threaded sheave forming rings mounted on the threaded portion of said threaded'pulleyhub, a plurale ity of slots in the threadedportion'of said sheaves forming rings, and a key carried inal keyway in the threaded periphery of said threadedy pulleyhub adapted t0 be inserted in the slots ofv said 4 I sheave forming rings When said rings have been rotated on said threaded periphery to desired axial positions on said threaded pulley hub, and va second pulley means on the other of said shafts operatively'related to theV-gro'oves formed by said sheave forming rings on said threaded pulvley hub comprising a second pulley mounted in fixed driving relationship on said other of said shafts, -a third pulley mounted coaxially with said slots inthe threaded poradjusting and second pulley about said other of said shafts, means for connecting said third pulley in lpositive driving relationship with said second pulley, means for' mounting said third pulley for relative axial movement to said second pulley and said sheave forming rings on said threaded pulley hubon said first shaft, and means for locking said third pulley in various of its axial positions.

3. In a; V-belt drive transmission for a pair of fixed center distance shafts, a pulley hub on one of said shafts, a threaded mounting means on the periphery of said hub for a series of axially adjustable sheave forming rings, a keywayf formed in Said periphery, a key means insaid keyway for locking said sheave forming rings in any desired axial adjustable position on said hub, a second pulley, a series of fixed sheave V-grooves formed in said second pulley', a hub portion on said second pulley, a third pulley axially slidable on said hub portion having other V-grooves formed therein, key driving means between said hub portion and said third pulley, and adjusting means for shifting and locking said third pulley in axial positions on said hub portion so as to maintain substantially accurate 'alignment of a" series 'of belts passing over said pulleysfor any relative axial adjustment'of said sheave forming rings of said first mentioned pulley.

HAROLD J. SIEKMANN. GEORGEJ. KASSELMANN.

REFERENCES CITED l The following references are of recordin the le of this patent: l l Y A UNITED STATES PATENTS j Great Britain 1905 

